Pressure regulation in a control system for automatic transmission

摘要

A control system for an automatic transmission, comprising: a fluid transmission unit (12) connected to an engine (10); a clutch (C1); a hydraulic servo (C-1); output RPM detecting means (47) for detecting the output RPM of the fluid transmission unit (12); oil pressure generating means for generating the oil pressure to be fed to the hydraulic servo; and a control unit (40). This control unit includes: booster means (105) for raising the oil pressure according to preset characteristics; change rate detecting means (103) for detecting the RPM change rate of the output RPM in a preset section at the applied of the clutch; and correction means (104) for correcting the characteristics by comparing the detected RPM change rate and a reference RPM change rate. The change rate detecting means (103) detects the RPM change rate only when the output RPM at the time of starting the engagement of the clutch (C1) is higher by a preset value than the maximum of the output RPM in the preset section.